Original subtitles

NARRATOR: January 2005, and Asia struggles to clear up

after the 2004 tsunami

and come to terms with the appalling destruction

that claimed the lives of over 250,000 men, women and children.

Tragically, this was not a one-off event.

These catastrophes have happened before

and will certainly happen again.

122 years ago, another natural disaster struck

in the same geologically active region of Indonesia.

This disaster was not caused by an undersea earthquake

of the kind that created December's tsunami,

but by the volcano Krakatoa.

This film is the story of that eruption,

but it is also an account of the first tentative steps

towards understanding the terrible power

of Earth's natural forces.

NARRATOR: On 27 August 1883,

the uninhabited volcanic island of Krakatoa

blew itself out of existence with an explosion

the equivalent power of 150 million tons of TNT.

( people screaming and yelling )

The eruption was so loud,

the sound was heard over a 12th of the earth's surface.

The shock waves reverberated around the entire planet

seven times.

These vibrations are airborne.

It's not coming through the ground.

This is not an earthquake.

NARRATOR: This explosion also caused giant tsunami--

the largest of them, twice the height of those of 2004.

Oh, dear God.

Turn her into the wave now!

NARRATOR: These enormous waves

wiped out 165 Indonesian towns and villages,

killing over 36,000 people.

Within hours, news of the disaster

was transmitted around the globe

and scientists of the time struggled to comprehend

the geological forces that caused the tragedy.

This film reconstructs the true stories of survivors,

from their accounts and diaries,

to piece together what happened

in the months leading up to the most famous eruption

of all time.

The eruption of Krakatoa over 120 years ago

has become a landmark in our understanding

of how volcanoes affect our planet.

Mike Rampino is professor of geology at New York University.

His research has been instrumental

in discovering why Krakatoa erupted with such force.

He's returning to Indonesia for the first time in 26 years.

The 1883 eruption of Krakatoa

is one of the most important eruptions

in the history of... of science,

I think probably the most important eruption

in terms of the history of volcanology.

For the first time,

a large explosive volcanic eruption took place

when there were enough observers spread around the world,

on land, on ships at sea,

to really get a global synoptic picture of what happens

when a large volcanic eruption takes place.

NARRATOR: Krakatoa's devastation was not wreaked by the eruption itself,

but like the disaster of 2004,

the massive death toll was caused by tsunami.

Volcanologist and writer Bill McGuire,

from Universy College London, is an expert in tsunami,

but those generated by Krakatoa in 1883

are of particular interest to him.

McGUIRE: No tsunami on the scale of Krakatoa are known.

I mean, they... these waves were really quite extraordinary--

I mean, a wall of water 120, 130 feet high,

40 meters high.

At the time, nobody would have understood

that a volcano which is, at closest, 25 to 30 miles to Java

would have posed any problems at all.

I don't think anybody thought it was going to come and get them,

because they didn't know about tsunami

certainly as a result of a volcanic eruption.

NARRATOR: Indonesia is a group of thousands of islands

in Southeast Asia.

Two of the largest islands in this archipelago

are Java and Sumatra;

separating them is a busy waterway

known as the Sunda Strait.

The volcano Krakatoa lies in the middle of this stretch of water.

Today, only a remnant can be seen of the 1883 volcano.

To understand what Krakatoa was like in 1883,

Mike Rampino has traveled

to the volcanic national park of Tennger Bromo in East Java.

Indonesia is the most volcanically active region

on the planet.

The country contains 17% of the world's active volcanoes.

The view at dawn from Mount Penanjakan

shows several of these volcanoes

within a few miles of each other.

This is the jewel of Indonesia,

but it's a beauty born from brute force.

McGUIRE: There's a kind of rule in geology

that the more beautiful the landscape,

the more dynamic the processes are

that create those landscapes.

And volcanism is one of the most dynamic processes

that exists on the planet.

And so we see these beautiful volcanoes,

these craters with steam and ash coming out,

and we think how beautiful, how dramatic, how gorgeous.

But it's what's underlying this,

what's going on underneath the ground, inside the earth,

that makes this such a dangerous situation.

NARRATOR: Indonesia has so many volcanoes and earthquakes

because of its geographical position.

The archipelago that starts in northern Sumatra

stretches over 3,000 miles south.

It has been created by the forces

where two of the tectonic plates

that make up the earth's surface meet.

The ocean floor of the Indo-Australian plate

and the Asian land mass of the Burmese continental plate

are in collision.

As they push against each other,

the heavier ocean floor is forced

underneath the lighter continental rock.

When these plates or slabs come together,

one pushes its way down back into the interior of the earth.

That process is called subduction.

And as that crust is pushed down

into the hot interior of the earth, the rock melts,

and some of that melted rock finds its way

back up to the surface through fissures and cracks

and erupts at the surface to form volcanic eruptions.

NARRATOR: Krakatoa lies directly above this subduction zone.

Volcanologists have pieced together

Krakatoa's eruptive history.

In 416 A.D., an ancient Krakatoa destroyed itself

in a massive explosion.

Over the next 1,200 years,

regular minor eruptions rebuilt the volcano.

These small eruptions helped release the pressure created

by the enormous geological forces beneath the island.

But over time, a plug of thick, viscous magma

formed in Krakatoa's throat,

preventing the gases and magma from escaping to the surface.

The eruptions ceased,

and by 1883, Krakatoa was a time bomb waiting to explode.

Within sight of Krakatoa

were the low-lying and densely populated coastlines

of West Java and southern Sumatra.

Situated at the southern tip of Sumatra was Ketimbang,

just 23 miles north of Krakatoa.

( birds chirping )

( quacking )

In 1883,

Ketimbang was a rural outpost of the Dutch colonial empire.

For over 250 years,

colonial rule in Indonesia had effectively reduced the locals

to tenants in their own land.

But an uneasy peace existed

and there seemed little that would disturb the daily life

of this heavily populated coastal village.

( man speaking local language )

NARRATOR: The controller of Ketimbang was Willem Beyerink.

As a Dutch official,

he was responsible for enforcing colonial law and order.

( speaking local language )

NARRATOR: Each morning, he would hold a clinic

for the administration of the affairs of the local people.

Beyerink was well versed in a number of skills

including Islamic law, local languages

and rudimentary geology.

( chirping )

With the local Indonesian population

serving as an extensive workforce,

Mrs. Beyerink ran a large colonial household

with numerous staff.

His name iJanni.

He's very beautiful.

( cooing )

NARRATOR: Krakatoa had been dormant for over 200 years,

but forces deep beneath the earth's surface

were about to wake this sleeping volcano.

By March 1883, subtle warning signs of the danger

that lurked below the volcano were felt on the surface

as faint tremors undetectable to human senses.

( bird squawking )

What's the matter with you?

( squawking, cage rattling )

What is it?

What are you so upset about, Jake?

Shh, shh, shh, shh.

There, now.

NARRATOR: Near Ketimbang lived fisherman and village elder Ajip.

Ajip was one of the local spiritual leaders

who acted as guardian to traditional Indonesian beliefs

passed from generation to generation.

( drum and pipe playing )

Although regarded as pure superstition by the Dutch,

the local belief was that the volcano Krakatoa

was home to the fearsome fire-breathing god, Oran Alijeh.

( drum beating )

When Krakatoa had erupted in the past,

it was because Oran Alijeh was angry, and Ajip was convinced

that one day soon the volcano would erupt again.

Across the Sunda Strait on the west coast of Java,

a series of lighthouses had been erected

to help navigate the waters.

The closest to Krakatoa

was Fourth Point Lighthouse at Anger.

As its recently appointed keeper,

Toemang would be one of the first to witness the beginning

of the eruption.

( Toemang conversing in local language )

He was married, with a son.

( family conversing )

( chuckling )

Passing even closer to Krakatoa

was the Dutch government steamer

the Gouverneur-Generaal Loudon

that regularly crossed the Sunda Strait.

The ship was under the command of Captain T.H. Lindeman.

The captain and crew of the Loudon

would be the witnesses closest to Krakatoa's eruption.

83 miles east of Krakatoa on the north coast of Java

is the port of Jakarta.

Today Jakarta is a busy hub for shipping in the Far East,

but in 1883 the city was the capital

of the Dutch East Indies.

Holland had been a dominant force

in the commerce of the spice routes.

Oriental spices and raw materials were highly prized,

and in the name of profit

the Dutch ruthlessly exploited Indonesia,

exporting everything from gold, rubber and sugar

to cinnamon, pepper and timber.

Large numbers of trading ships

would travel back and forth to Europe.

Each one would dock in Jakarta--

or Batavia, as it was then known.

In 1883 Dr. Van der Stok

was the director of the Magnetic and Meteorological Observatory

in Batavia.

He was responsible for monitoring seismic activity

throughout Indonesia, and his observations

of the early stages of Krakatoa's eruption

would help modern volcanologists understand

why the volcano exploded with such force.

Also stationed in Batavia was J. Schurmann,

an energetic young geologist

with a basic understanding of volcanology.

Schurmann's expedition to Krakatoa

would provide a firsthand account of the erupting volcano,

as well as valuable samples of pumice.

( knocking )

Schurmann.

Director.

Have you come to return my books?

Ooh, I've not quite finished with them yet.

You know the 11th commandment...

I find ten hard enough.

"All books borrowed must be returned

on pain of hellfire."

Is God a librarian?

Well, if he was, you'd be struck down dead

where you stand.

I was wondering if you had anything

on animal behavior.

There's an old Japanese story about catfish.

They behave oddly just prior to an earthquake.

Really.

Well, you've seen for yourself how dogs

and domestic animals become disorientated

just before a thunderstorm.

I don't believe I have anything on the subject.

That only goes to show there's a book to be written on it.

Just think-- animal behavior could be used

to predict the weather, even earthquakes.

I've heard that the Chinese use grasshoppers.

If we could relate the results of your instruments

with observed changes in animal behavior...

Enough. This is hardly science.

Of course this is science!

Everything is science.

( sighs )

NARRATOR: In the 1800s, science and technology

were marching mankind into the modern era,

and the public's curiosity about the natural world

was at an all-time high.

McGUIRE: The Victorian age

is a great age of discovery and observation.

Everyone was keen on recording things,

natural phenomena.

So barometers existed in gentlemen's clubs here, there

and everywhere.

People were very interested in the weather in particular,

and so these different measuring devices started to crop up

all over the world, and that was fortuitous

because it meant when the eruption actually happened

not only could the events be recorded in Indonesia itself

but the distant effects

could be recorded right across the planet.

Well, that all seems in order.

Thank you.

Anna.

I thought we might take a walk this afternoon.

I'm rather busy.

I know, but I can hardly wait until you're not busy, can I?

Then I would wait forever.

Well, perhaps tomorrow, hmm?

Oh, no, I can't.

I have a report to write.

I have to get it off to Batavia tomorrow.

And if your report is one day late...

will it matter?

Why can't you accept that I have a job to do?

( rumbling )

NARRATOR: As controller of Ketimbang, one of Beyerink's responsibilities

was to report large tremors to his superiors in Batavia.

But having no clue where the tremor had come from

or what had caused it, he was unaware of the danger

that lay only 23 miles out to sea.

( key clicking )

Just before midnight on the 9th of May, 1883,

intense pressure building deep beneath the earth's crust

broke through the line of weakness

directly below Krakatoa.

Magma moving towards the surface

split the crust apart, creating a large tremor.

( rumbling )

( wind howling as rumbling continues )

What the lighthouse keeper witnessed is now recognized

as the first documented warning sign

of the beginning of Krakatoa's 1883 eruption.

McGUIRE: In May 1883,

the lighthouse keeper here at the Fourth Point Lighthouse

actually saw the sea sort of go flat calm just for an instant,

and he would have thought this was rather strange.

Now, what he was seeing then

was the result of fresh magma actually breaking rock

on its way from deep down within the crust to the surface.

When that happens,

when the rock breaks it generates earthquakes,

and as those earthquake waves travel through the sea,

they cause it to freeze, if you like.

It's the same thing that you see

when depth charges explode beneath the suace,

and so that's what he would have seen.

He would have seen a normal behavior of the waves.

Then they would have frozen for an instant,

and then they would have carried on again,

and that would have been, obviously, rather odd to him.

NARRATOR: To momentarily freeze the waters of the Sunda Strait

required incomprehensible geological forces.

After 200 years of dormancy,

Krakatoa was about to wake from its slumber.

In the early 1800s, the volcanic island of Krakatoa

had been used by the Dutch as a penal colony.

The island had also served as an outpost

for naval reconnaissance

But by 1883

Krakatoa was uninhabited and only frequented by fishermen,

who used the surrounding waters as a rich hunting ground,

and the fertile jungle for timber to build their boats.

But all that was about to change.

( rumbling )

11 days after the tremor at the lighthouse,

in the early morning of the 20th of May,

the tranquil island of Krakatoa burst into life.

Intense pressure building beneath the most northern crater

was finally released.

( rumbling and exploding )

What's happening?

There, Captain.

Dear God.

Hold this course as best you can.

Captain.

NARRATOR: The initial eruption

was witnessed by people aboard a dozen ships in the Sunda Strait,

including Captain Lindeman on the Gouverneur-Generaal Loudon.

Moments after the eruption,

shock waves were felt 23 miles north in Ketimbang.

( dog barking, earth rumbling, baby crying )

( dog barking )

Minutes later, the blast was felt 83 miles away in Batavia.

The shock wave was registered in Dr. Van der Stok's observatory.

Among his many instruments

was a magnetic declinometer fitted with floating needles

that were so sensitive they detected the tiniest movements

through the ground or through the air.

Using the readout from the declinometer,

Dr. Van der Stok deduced he was dealing with an air blast

caused by an explosion nearly 100 miles away.

( knock at door )

SCHURMANN: Did you register a tremor?

Does that correlate with your instruments?

It's not an earthquake.

Take a look at this.

The needle has been moving

in a vertical plane.

These vibrations are airborne.

It's not coming through the ground.

It is not an earthquake.

Then volcanic.

I think so.

At last!

I have always wanted a volcano.

What do we have on the subject?

NARRATOR: But even Van der Stok could not have predicted

the scale of devastation Krakatoa would wreak.

Because he witnessed the eruption firsthand,

Captain Lindeman's log now forms a vital part

of a body of information about the eruption.

LINDEMAN: "On the 20th of May at 10:30 in the morning,

a volcanic eruption was observed on the island of Krakatoa."

"We saw from the island a white cumulus cloud rising fast.

"It rose almost vertically until after about half an hour,

"it had reached 11,000 meters.

"Here it started to spread like an umbrella,

"as it had reached the height of the westerly winds.

Soon, only a small part of blue sky was seen on the horizon."

NARRATOR: This initial eruption, however, was only the prelude

to a far greater explosion yet to come.

( Krakatoa rumbling )

Krakatoa had finally woken from its slumber.

NARRATOR: Volcanologist Mike Rampino is crossing the "Sea of Sand"--

a vast volcanic plain--

on his way to one of the most active volcanoes in Indonesia.

Mount Bromo has many similarities to Krakatoa.

It is fueled by magma generated from the friction

of the Indonesian subduction zone,

and its crater is approximately the same size as Krakatoa's.

But Bromo continuously releases the pressure beneath it

and is known to have erupted 50 times in the last 200 years,

and so never on the scale of Krakatoa in 1883.

RAMPINO: The initial eruption of Krakatoa on May 20, 1883 was typical

for the beginning of an explosive volcanic eruption.

There was a sudden explosion

and a rise of a column of ash and steam and gas,

in this case, very rapidly, up to a height

of about 30,000 feet above sea lel.

What had happened is a viscous plug

of congealed magma and rock was sitting

in the throat of that volcano for 200 years,

and finally the pressure below it built up

to the point where the rock cap broke.

That released the pressure

on the magma chamber inside the volcano,

and that's like popping the cork on a champagne bottle.

In fact, it's like shaking up a champagne bottle first

and then popping the cork.

( rumbling loudly )

This violent eruption was the opening salvo

for a series of eruptions that were to take place

over the next few months.

( explosion )

( clicking )

NARRATOR: As eyewitness reports of the eruption

flooded into Batavia,

the authorities ordered Willem Beyerink,

as the closest official to the volcano,

to go to Krakatoa

and report on the scale of the volcanic explosion.

The following morning, Beyerink and the local fisherman Ajip

began their journey to the island of Krakatoa.

The volcano that normally dominated the horizon

was now invisible, shrouded in clouds of acrid sulfurous gas.

Their progress was painfully slow.

( coughing )

Stop! Stop!

( explosion )

BEYERINK: Turn around!

( speaking local language )

NARRATOR: Although Beyerink had only ventured

within sight of Krakatoa, it was clear to him

that the volcano was now a serious threat.

( telegraph clicking )

NARRATOR: On his return, a concerned Beyerink wired a report

of the eruption to Dr. Van der Stok

at the Magnetic and Meteorological Observatory

in Batavia.

The governor general was immediately informed.

By the 27th of May, 1883,

the large eruptions on Krakatoa had abated.

During this relative lull in activity,

an eerie calm now shrouded the mountain.

Driven by scientific curiosity,

Schurmann and Van der Stok set foot on Krakatoa to investigate.

As they began their ascent up the slopes of the active crater,

they saw that large areas of the once forested island

now lay charred and smoldering.

What could have done this?

These trees have been completely flattened by some immense force.

The entire forest has been stripped bare.

What do you make of it?

Well, it's as if some superheated whirlwind

has torn down the mountain.

It's remarkable!

Indeed.

NARRATOR: Schurmann's report to the authorities

now provides invaluable evidence

of the devastation on the island.

SCHURMANN: "Following in the footsteps

"of the bravest, or perhaps the most foolhardy,

"we climbed the bare hills,

"which did not offer any obstacles

other than the loose ash."

( men coughing )

"Horrible was the view of that somber and empty landscape,

which portrayed itself as a picture of total destruction."

"Foul-smelling smoke permeated the landscape,

causing us to gag."

"In addition to the smoke,

"one also recognized amongst the gaseous products sulfuric acid,

which made itself known by its smell."

NARRATOR: The samples collected by the expedition

are now a vital record of the volcanic material

ejected by Krakatoa in the early stages of eruption.

I expect this is what Hell looks like.

( muffled explosion )

( explosion )

We should be getting back.

I want to see the crater.

We don't have the time.

I'm going up there!

Schurmann, no.

You've become too comfortable, stuck in your observatory.

Come on!

( chuckles ): Come!

Come on!

Not too far now, Doctor.

Not too far.

SCHURMANN: "Soon every sign of vegetation disappeared

and all we could see was the roaring column of smoke."

"We climbed the last hill

and we were standing at the steep edge of the crater wall."

( lava roiling )

Who thought Hell could be so beautiful?

( laughing )

You really are quite mad, Schurmann, aren't you?

( both laughing )

NARRATOR: Schurmann and Van der Stok believed

that the worst of the eruption was over.

Little did they know that in three months' time,

the entire island of Krakatoa

would have blown itself out of existence.

NARRATOR: Volcanologist Mike Rampino

is at the lip of the crater of Mount Bromo in East Java.

Bromo's crater is a similar size

to the one Schurmann would have seen on Krakatoa.

RAMPINO: Schurmann, in a sense, was one of the first volcanologists.

At that time, volcanology was in its infancy

and we didn't know much about the behavior of volcanoes.

And, in fact, the study of Krakatoa

was the first real study of a volcano

that began to give us information

about how volcanoes work.

And Schurmann actually did a very valuable thing

by collecting samples of the material

that had been erupted by the volcano

during its earliest stages of eruption.

( camera shutter clicks )

Clearly, when Schurmann walked across Krakatoa,

he should have known that it was a dangerous place to be.

NARRATOR: Schurmann's party had no real understanding

of just how dangerous their expedition had been.

Today, volcanologists like Mike Rampino fully understand

the deadly forces that had stripped the slopes of Krakatoa,

forces known as pyroclastic flows.

RAMPINO: They were quite lucky to be there during a time

when the volcano was less active,

because the area had been devastated

by pyroclastic flows and surges--

hot mixtures of ash and gas.

( rumbling loudly )

NARRATOR: Krakatoa's first eruption

had thrown fine particles of ash high into the atmosphere,

but the real danger lay closer to its flanks.

Heavier material had cascaded down the sides of the volcano

as superheated debris.

( rumbling loudly )

Anything standing in the way of this pyroclastic flow

would have been incinerated instantly.

( plucking stringed instrument )

NARRATOR: By the end of May 1883,

Krakatoa, the volcano that had violently awoken

after 200 years, returned to relative calm.

For three months after Schurmann's expedition,

all that was noticed on the island

was a continuous plume of smoke and the occasional rumble.

Because of the widespread belief that the eruption was over,

life in the coastal communities

of West Java and southern Sumatra returned to normal.

( moped motors humming )

McGUIRE: It's fairly common during many explosive eruptions,

during the early stages that... that you get some activity

and then things quieten down again.

This is the really dangerous thing about explosive eruptions.

It's almost impossible to predict

when the climax is going to .

In the case of some eruptions, it can come within a week.

In the case of Krakatoa, it came months after activity started,

and there's a danger always

that once activity has died down, people are going to say,

"Well, that's it, let's forget about it,

everything's... we're all safe now."

But that often isn't the case.

NARRATOR: Along the coastlines of West Java and southern Sumatra,

the morning of Sunday, the 26th of August, 1883,

was as any other.

( thunderous explosion )

( explosions continue )

At six minutes past 1:00

on the afternoon of Sunday, the 26th of August, 1883,

all three craters on the volcanic island of Krakatoa

erupted in a massive volley of explosions.

The enormous pressure that had been building

for hundreds of years

was suddenly released.

( explosions cracking )

What was to become the most devastating volcanic event

in recorded history...

had begun.

The densely populated communities

living within sight of Krakatoa,

on the coastal areas of West Java and southern Sumatra,

now had only hours before the full force of the volcano

would devastate the area.

McGUIRE: Once the volcano really started getting going

at lunchtime on the 26th,

things were going to go from bad to worse.

There were big explosions every ten minutes or so,

and these merged together to form a column of ash and debris

which extended up to something like 25 kilometers, 18 miles,

into the atmosphere.

( rumbling )

There was heavy ashfall,

there was a lot of pumice falling

on ships out in the straits,

and by late afternoon everywhere was pitch black

and you probably could hardly see

your hand in front of your face.

You would have had earthquakes going on,

accompanying these explosions.

At the same time, you would have been having

these flows of hot debris-- called pyroclastic flows--

entering the sea,

and the sea would have been getting increasingly agitated.

( thunderous explosions )

NARRATOR: The ship closest to Krakatoa that afternoon,

just 12 miles away,

was the Gouverneur-Generaal Loudon.

Keep her away from the coast!

( straining ): We mustn't be drawn inland!

NARRATOR: Hot, sticky volcanic ash fell from the dark clouds

smothering the ship.

Get that paraffin off the deck before it explodes!

Overboard-- all of it!

Overboard! Overboard!

NARRATOR: The heavy rain of ash and pumice spread 23 miles north

to Ketimbang in southern Sumatra.

McGUIRE: They would have experienced the ash starting to drift down,

and then maybe sort of pellet-sized bits of pumice

and bigger bits of pumice falling.

And, generally, just this increase

in the amount of material falling out of the sky.

When it got really dark, when the ashfall was so heavy

that you couldn't really see anywhere,

then you would have...

I think temperatures would probably have risen

because beneath very heavy ashfall

it does get very sticky and muggy, and you can...

It's not hot, but it is warm,

and they would have experienced that.

NARRATOR: At 5:30 the following morning,

the first of four truly cataclysmic explosions

occurred on Krakatoa.

The volcano erupted, literally ripping itself apart

in an explosion equivalent to the power

of a thousand atomic bombs.

Why this small volcanic island in the Indonesian archipelago

exploded with such ferocity

has puzzled volcanologists for almost a hundred years.

In order to answer that question,

Mike Rampino is on his way to Krakatoa,

to the only part of the volcano that remains today--

the island of Rakata.

Rampino first visited Krakatoa in 1979

to pick over the remains of the eruption

in search of vital evidence.

He's now returning with local guide Samsul

to confirm his latest theory.

RAMPINO: The first time I was here with a group of scientists,

we were looking at the pyroclastic deposits,

the pumice deposits, of the 1883 eruption

specifically to try and figure out

what the triggering mechanism was

for the enormous explosion that took place in August 1883.

NARRATOR: The initial theory to explain

the extreme violence of Krakatoa's eruptions was that

seawater seeped inside the volcano,

and mixed with the magma to create the huge explosions.

This theory did not stand up to scrutiny.

RAMPINO: We were testing the idea

that seawater got into the volcanic vent

and that's what caused the explosion.

What we found was that usually those kinds of eruptions

have very, very fine-grained pumices.

The pumices are fragmented by the reaction with the water.

And here at Krakatoa,

I've seen that the pumices are rather large.

And so the lack of fine-grained material suggests

that it wasn't seawater getting into the vent

that triggered the eruption.

NARRATOR: If seawater didn't trigger these huge explosions, what did?

Hidden in Rakata's dense jungle are thick layers of pumice

ejected from the volcano in 1883.

This volcac rock is a permanent record

of what happened deep beneath Krakatoa

and explains why it erupted with such exceptional violence.

Here we could find huge charcoal

and also pumice everywhere.

Here.

Here's one.

Good, thanks.

Oh... this is really big pumice.

Huge pumices.

Wow...

RAMPINO: And the charcoal here,

trees that were killed by the ash.

So, a beautiful sequence of pumices.

Finer grain...

another pumice layer, but small pumices

and then the pyroclastic flow deposits

going all the way to the top of the outcrop.

SAMSUL: Jeez, like this?

Yes.

The whole eruption sequence, you can see it here.

NARRATOR: Molten rock lying inside Krakatoa's magma chamber

for 200 years of dormancy

was light in color and cool in temperature.

After the initial eruption in May,

the magma chamber was part emptied

and that void was filled from below by dark-colored magma

that was extremely hot in temperature.

It was a lethal cocktail.

As the two mixed together,

the intense heat of the dark magma

created huge amounts of gas that expanded,

eventually creating enough pressure

to cause the volcano to erupt with terrifying force.

So this is the mixed pumice.

It's got the light material and the dark material--

two different kinds of magma--

that triggered the 1883 eruption.

This light-colored magma was sitting there for a long time

in the magma chamber.

And then this dark-colored stuff came in from the bottom,

heated it up and caused it to overturn,

and for the gas to begin to come out of the magma

and the pressure built up.

And that's what caused the volcanic eruption, yes.

Yes.

( explosions )

NARRATOR: This mixing of two magmas beneath Krakatoa

was the direct cause of the massive explosions.

But when combined with the volcano's unique position

in the Sunda Strait,

these explosions generated a series of giant tsunami.

Some would be the largest waves ever witnessed.

( bubbling )

At 6:44 on the morning of the 27th of August, 1883,

the second massive eruption occurred on Krakatoa.

Pyroclastic flows of dense material

cascaded down the flanks of the volcano,

and immense submarine slides generated giant shock waves

in the surrounding ocean.

In the Sunda Strait, the shock waves were witnessed

as huge crests of water.

Dear God.

Turn her into the wave, now!

As fast as you can!

Lash yourselves down!

NARRATOR: When these first waves reached the coastline of Java,

they slowed and reared up to enormous height,

revealing the full horror of a tsunami.

( shouting in local language )

NARRATOR: Today, all that's left of the Fourth Point Lighthouse

are the remains of its foundations,

a six-foot-thick brick buttress.

Despite its obvious strengths,

the structure was unable to survive

the enormous force of the tsunami.

McGUIRE: The lighthouse seemed as if it was going to survive,

but then it was hit by a block of coral

estimated to weigh something like 600 tons,

which had been scraped up from the seabed

and which had crashed into the base of the lighthouse.

And it looked as if it separated the lighthouse

from its base,

and the whole thing toppled over

and it was then broken up and carried off in the water.

NARRATOR: Two years after the destruction of the Fourth Point Lighthouse,

a new one was built, just yards from the original.

McGUIRE: The new Fourth Point Lighthouse,

it's 40 meters high,

which is just about the height of the largest wave.

And looking down from here, it's almost unbelievable

that you could get a wave of that height.

It would have completely trashed the whole region.

I mean, a wave of 40 meters...

And, remember, this isn't just like

a single wave that crashes onto a beach.

Tsunami have very long wavelengths,

so the waves can be hundreds of meters

or several kilometers long.

So they come in as a wall of water,

and that wall just keeps coming--

and it would have just wiped out everything entirely.

NARRATOR: A total of 19,600 Javanese died

on this stretch of coastline alone.

These black-and-white photographs of the destruction

taken over 120 years ago

are, sadly, all too familiar today.

McGUIRE: The 2004 tsunami was more destructive

in the sense that it killed more people over a large area,

and that is because such a big area of seabed

was jolted upwards and that sent these waves out.

The waves generated by the Krakatoa eruption

were much, much bigger, but they lost energy very rapidly,

so they didn't travel any great distances.

NARRATOR: The Fourth Point tsunami

stripped the sand from the beaches

and destroyed everything in its path.

It seemed like the end of the world...

but worse was yet to come.

McGUIRE: The morning of the 27th

must have been absolutely appalling,

particularly after the...

these gigantic explosions have started

and after the first great waves had destroyed

many of the communities along the coast of Java

and southern Sumatra.

people had already... many people had already died,

others were terrified.

and I think people by then must have begun to wonder,

you know, is this the end of the world?

Is this just affecting us here

or is everybody experiencing this?

NARRATOR: At two minutes past 10:00

on the morning of the 27th of August, 1883,

Krakatoa exploded once more,

this time with such extreme intensity

that it was heard over a 12th of the earth's surface.

The sound of the detonation was carried 2,000 miles south

to Perth, Australia, and 3,000 miles west to Rodriguez Island

in the Indian Ocean.

It remains the longest distance traveled by any airborne sound

in recorded history.

McGUIRE: This is the climax

of the whole eruptive sequence,

one of the loudest noises-- if not the loudest noise--

ever heard by modern humans.

( rumbling and thundering )

NARRATOR: When Willem Beyerink, the controller of Ketimbang,

witnessed this huge eruption,

he realized that the explosion would produce

a tsunami of enormous size.

( people yelling )

Anna!

( Anna calling out )

( parrot squawking )

( baby crying )

NARRATOR: The tsunami generated by Krakatoa

would travel across the Sunda Strait

at approximately 60 miles per hour,

taking just 20 minutes to travel the 23 miles to Ketimbang.

( people yelling )

Anna!

( baby crying )

Anna!

Thank God, thank God!

We have to get to higher ground.

NARRATOR: Fortunately for the Beyerinks,

Ketimbang was situated at the foot of Mount Rajabasa.

( baby crying )

( screaming and yelling )

( baby crying )

NARRATOR: The Beyerinks escaped the clutches of the tsunami

by climbing the slopes of Mount Rajabasa

to 400 feet above sea level.

( Anna coughing )

NARRATOR: By mid-morning on the 27th of August,

8,038 people had died around Ketimbang.

( baby continues crying )

Leaving death and destruction in its wake,

the tsunami funneled up the Lampong Bay,

continuing to slow in speed and gather in height.

( engine chugging softly )

McGUIRE: Tsunami are all incredibly affected by topography

and they will get funneled by bays, by estuaries,

by harbors et cetera,

and that happened here in Lampong Bay.

The wave devastated the entire low-lying region

around the bay here.

The fishing communities on Sumatra

would have had no chance at all.

The wave that came up this bay was 24 meters high--

you're talking maybe 80 or 90 feet high.

This would have been a wall of water

which just continued to come inland for several minutes.

There would have been no chance to survive

unless you were closer to high ground

and could actually make a run for it--

because the waves would be traveling

as fast as a sprinter could run,

and most people wouldn't have a chance of outrunning that.

NARRATOR: At the head of the Lampong Bay,

lying directly in the path of the tsunami,

was Telok Betong, the largest port in southern Sumatra.

The entire town was washed away, killing a further 2,263 people.

This is the mouth of the River Koeripan,

which is at the head of the Lampong Bay.

It's an excellent example

of what Telok Betong would have looked like

after the tsunami had funneled up the bay

and then gone back out again--

a scene of complete devastation, really,

mud covering everything, trees sheered off

so that all you see are the stumps sticking up

and no sign at all of human habitation.

NARRATOR: In the harbor at Telok Betong

was the Dutch government steamship the Berouw.

Its mooring buoy now lies as a forgotten monument to the dead.

This is the only memorial

for the Indonesian victims of Krakatoa.

With similar power to the 2004 tsunami,

the wave generated by Krakatoa

picked up the steamship Berouw and her crew of 28

and carried them inland.

Their final resting place can be found

almost two miles up the River Koeripan.

McGUIRE: The Berouw was already suffering

because the seas were getting very agitated.

And then, a big tsunami tore the ship from its mooring buoy

and dumped it up this river here.

This is where it all ended

for the Berouw and her 28 dead crewmen,

1.8 miles up the Koeripan River,

about 30 feet above sea level.

When the boat was found,

which was about a month after the eruption,

it was actually in very good condition.

It was stretched across the river here.

It was full of ash and mud,

but its engines were in working order,

and if it could have been got back to the sea

it could have actually been seaworthy again.

But its real fate was much more ignominious than that.

It just sat here rusting away for many decades,

virtually disappearing after 50 years or so.

Its huge boiler remained behind

until that was washed down in a flash flood in 1979

and finally cut up for scrap.

( rumbling )

NARRATOR: At 10:45 on the morning of the 27th of August, 1883,

the fourth and final eruption tore Krakatoa apart.

When the ash and smoke cleared,

the shell of the volcano had collapsed

beneath the surface of the water into the empty magma chamber.

All that was left was a remnant of the volcano

known as Rakata,

and the existing islands of Verlaten and Lang.

One of the last casualties of Krakatoa

was the Beyerinks' child.

Burnt, choked by ash and poisonous gas,

the baby eventually succumbed to the trauma.

Madame.

( Anna screams and cries )

NARRATOR: Reports following the eruption

reveal that the lighthouse keeper miraculously survived

the tsunami.

His wife and child did not.

Despite his personal tragedy,

records show that Toemang stood by his post,

performing his duty as keeper,

warning passing ships in the Sunda Strait.

Captain Lindeman and the crew of the Gouverneur-Generaal Loudon

also survived the ordeal.

( clicking )

Within hours of the final eruption,

the dramatic news was being transmitted around the world.

The names and obituaries of the 37 Europeans who died

were widely published,

but the names of the thousands of Indonesian victims

were never recorded

and their personal details have been lost in time.

In total, 36,417 people died

and 165 towns and villages were destroyed.

It remains to this day

the largest known death toll from any volcanic eruption.

McGUIRE: Most of those deaths resulted

from water, from the oceans, from the tsunami,

not from the direct effects of hot rock.

And that's something that many people don't appreciate

about volcanic eruptions, even today,

that the... the big killers include tsunami

and include things like volcanic mud flows.

And, in fact, a number of the great disasters--

volcanic disasters-- have been caused

by these relatively indirect effects.

( rumbling )

NARRATOR: But it wasn't just Indonesia that was changed by Krakatoa.

11 cubic miles of rock and ash

had been blasted into the atmosphere,

and for many years after 1883

the effects of the eruption would be felt around the world.

RAMPINO: If you add up all the material that was erupted by Krakatoa

and brought it to Manhattan,

you could cover the island of Manhattan

to a depth of about 200 feet.

That's the volume of material ejected

during the massive phase of the Krakatoa eruption in 1883.

NARRATOR: No atomic bomb blast can rival the sound

that the final eruption made.

The shock waves from the explosion

reverberated around the globe seven times

and were still detectable five days later.

McGUIRE: Very few people appreciate

how cataclysmic volcanic eruptions can be

and, in fact, 500 million people live within the danger zones

around active volcanoes today.

That's more than one in 12 of the earth's population.

But the thing is,

volcanoes aren't always going to sit there looking pretty.

Every now and again

they generate these cataclysmic eruptions.

That's something that Krakatoa taught us.

And I think people only then began to realize,

certainly scientists, that a single volcanic eruption

could be so powerful as to affect everyone on the planet.

NARRATOR: Krakatoa erupted in a Dutch colony,

but it was left to British scientists

to document and analyze its effect around the world.

Dr. Eleanor Highwood is a meteorologist

at Reading University.

She is visiting the Royal Society in London.

The society was established in 1660

to promote the study of natural phenomena.

And in January, 1884, it set up a Krakatoa committee

to investigate the effects of the eruption on a global scale.

Dr. Highwood studies changes

in climate and atmospheric conditions

after large volcanic eruptions, and the Royal Society

contains the most comprehensive collection of material

devoted to Krakatoa.

Ah, are these for me?

Yes, they are.

These are the papers relating to the Krakatoa Committee

and that's the committee minutes.

Okay.

Thank you.

NARRATOR: The Krakatoa Committee collated in meticulous detail

documentation from all over the world.

They collected newspaper cuttings and ships' logs,

commissioned scientific reports

and even invited the public to write in

with eyewitness accounts of the effects of Krakatoa.

The result was the most comprehensive report

about a volcanic eruption of its time.

HIGHWOOD: So this report starts right from the start

of the volcanic eruption, talking about the geology,

and then it... it covers everything.

It goes through the sea waves.

There's time scales for the atmospheric waves

passing round the globe seven times,

and they're recorded everywhere from Australia

right the way through to Oxford--

really a global phenomenon.

And then an awful lot on optical phenomena--

so, twilight effects and sunsets, sunrises.

So, August the 29th, from Japan--

"The sun was blood red with jetlike smoke

passing across its face."

A month later or so, Haslemere in Surrey--

"Light pink cirrus stripes at sunset."

Buenos Aires, the last days of September--

"The glows began.

"They lasted one hour, 30 minutes.

The sun and moon were occasionally colored."

And there's evidence here that this continued

for four or five years.

This was really the first evidence

that started to give meteorologists a good idea

of how matter is transported through the atmosphere.

NARRATOR: These changes in the night sky, within days of the eruption,

confirmed the existence of high-speed, high-altitude winds

that transported volcanic particles

through the atmosphere.

Today, these winds are known as jet streams,

and their discovery has played a pivotal role

in our understanding of the weather.

NARRATOR: The eruption of Krakatoa

propelled 11 cubic miles of ash and dust into the air.

The heavier material fell back to Earth,

but the tiniest particles and sulfur dioxide gas

continued to rise into the upper atmosphere.

Within days, carried by jet streams,

this aerosol of tiny droplets of sulfuric acid

veiled 70% of the world

and reflected solar radiation back to space.

The result was an overall cooling

of the earth's temperature by half a degree Celsius.

But this process had another impact on the globe--

it turned the skies... blood red.

Housed in the archive of London's Science Museum

is perhaps the most vibrant example

of how Krakatoa affected weather systems

on the other side of the world.

Curator Wendy Sheridan is showing Dr. Highwood

the work of Victorian painter William Ascroft.

Between September 1883 and 1886,

Ascroft sketched the changing skies from Chelsea, West London.

The result is a series of extraordinary oil pastels.

SHERIDAN: This is the first panel of 72

of 533 sketches

that the artist William Ascroft started sketching in 1883

when he noticed changes in the colors of sunsets,

and he spent four years in virtually the same place

sketching them, timing each sketch

according to the changes in the colors.

So this sequence shows some particularly vivid colors--

some very strong red and yellow coloration

through the whole of the atmosphere.

So these really vivid reds are a product of the fact

that there was aerosol in the stratosphere

that had been transported from the Krakatoa eruption,

and light passing through that layer is scattered,

but it's scattered differently depending upon what color it is.

And so we tend to see reds more strongly

in sunsets and sunrises.

NARRATOR: In an age of black-and-white photography,

Ascroft's unique work acts as a time-lapse account

of how Krakatoa, thousands of miles away,

directly affected the British skyline.

Over 120 years later, the story of Krakatoa is far from over.

Although the eruption in 1883

almost completely destroyed the entire volcano...

( explosion )

from its ashes, a new one is emerging.

NARRATOR: In the middle of the old caldera

lies Anak Krakatau-- the "child of Krakatoa"--

and it's active and growing.

Mike Rampino set foot on Anak 26 years ago.

He's now returning there with Dr. Rudi Hadisantono

from the Volcanological Survey of Indonesia.

Rudi accompanied him on his first trip.

HADISANTONO: This must grow so fast...

RAMPINO: Very fast growth,

because there was almost no forest here

when we were here last time.

So, the... the lava flows on the other side of the island...

on this side of the island, mostly jungle, but...

So this is the end of the forest

and there is Anak.

Twice as big as it was 25 years ago

when I was here with you.

Yeah, right.

NARRATOR: In its short life, the volcano has injured five tourists

and claimed the life of one--

hit by a lava bomb exploding out of the crater.

There's now an official warning

advising against venturing onto the island.

( men panting )

It's hard to climb.

Yeah, very steep.

( muffled explosion )

NARRATOR: Anak Krakatau first revealed itself in December 1927,

when it erupted violently

just beneath the surface of the water.

( explosion )

Since then, it has been erupting with increasing intensity

and growing rapidly, at a rate of 15 feet every year.

Today, Anak is over 2,600 feet high,

almost the same height Krakatoa was in 1883.

It covers one and a quarter square miles,

and between 1992 and 2000

ejected over 50 million tons of material.

It appears that Krakatoa is preparing itself

for another huge eruption.

RAMPINO: Almost at the main crater here.

HADISANTONO: Yeah. It's here.

Ah! Wow! Wow!

We get on the crater.

Look at the size of this.

What do you think is the diameter?

It looks about 200 meters across, 600 feet across.

Yeah, yeah, I think so.

Yeah. Yeah.

And the fumaroles here.

Yeah.

I'm choking, though, from the sulfur dioxide.

RAMPINO: We're standing here on, on the active volcano, Anak Krakatoa.

The old peak of Krakatoa is behind us

and the old craters, the eruption centers for the 1883 eruption

were on this same line.

So that's why volcanologists now think

that there was a... a fault line,

a fissure that ran along in a straight line here,

along which all of these volcanic centers were erupting.

( hammer clinking )

NARRATOR: Anak Krakatau is being carefully monitored

by the Volcanological Survey of Indonesia,

and particular attention is being paid

to the viscosity of the magma.

Yeah. What's the temperature?

110.

110 Celsius.

And then this...

RAMPINO: In the future, we would expect that Anak Krakatoa

will build a larger and larger volcano here,

but eventually things going on inside the earth

will cause changes in the type of magma that's coming up,

and the more viscous it is,

the more chance of congealed magma sealing

or blocking the throat of the volcano,

the more chance of an explosive eruption.

NARRATOR: Anak Krakatau will continue to grow in size,

and it's a geological inevitability

that sooner or later, processes deep beneath the volcano

will cause Krakatoa to erupt once more with paroxysmal force.

As we know from the tragic events of the tsunami of 2004,

history repeats itself.

And for the people of Indonesia,

living in this geologically unstable region,

the unpredictability of nature is all too real.

RAMPINO: The tragedy of Krakatoa was it was located

in the middle of the Sunda Strait

surrounded by water and surrounded by coastlines

that were fairly densely populated--

very low-lying coastlines,

unprotected in any way from... from these kinds of waves.

NARRATOR: The work of Schurmann, Van der Stok

and the Royal Society was an important step

in advancing modern science's understanding

of how these geological processes work.

But the challenge for the future

is not just to understand these forces, but to predict them.

The hard lessons learned

are that the destructive power of nature

should never be underestimated.

Krakatoa and the tsunami of 2004 remind us that we live

on an active planet where the earth's crust

is constantly destroyed and regenerated.

These immense geological forces going on beneath us

reveal themselves in unforeseen ways

and with terrible consequences.

To order Krakatoa on videocassette or DVD,

call PBS Home Video at 1-800-PLAY-PBS.

Captioned by Media Access Group at WGBH access.wgbh.org